What is the proper symbol for solder jumper? I have created my own symbols and my own footprints for normally closed and normally open styles based on what I seen somewhewre, but an assembler who is fresh from school and pumped and got the task of prototyping the design on perfboard was puzzled with it, so I got unsecure about my symbols
It is still common to represent this as an optional 0 Ohm resistor and many designs still use a 0-Ohm SMT link; you just have to remember to use the right footprint for the artwork if you want to use a solder bridge.
Speaking of this schematics, what is the purpose of the jumpers here?
I use an extra PCB layer to represent my jumper links. There are probably many technical disadvantages, but so far I’ve only worked on single-sided designs.
I just made my own symbols for this as well, and then noticed that there are already jumper symbols in KiCad, Jumper_NC_Small and Jumper_NO_Small. Whoops! I called mine Solder_Jumper_NO and Solder_Jumper_NC.
It might not be a widespread standard, but solder jumper/bridge symbols aren’t unheard of:
http://rapidtables.com/electric/solder-bridge.htm
One hiccup: the open solder jumper symbol looks kind of like some versions of the symbol for a neon bulb but without the enclosing circle. I doubt they would get confused in most circuits. 
http://www.bristolwatch.com/ele/neon.htm
It seems that which symbol is best depends on the situation. To me, the existing symbols slightly imply that a male header and a shorting jumper need to be installed, unless the footprint obviously resembles a solder jumper (not visible from the schematic). Best for end user configuration.
A dedicated solder jumper or solder bridge symbol indicates footprint intent (and lack of an installed component) on the schematic better, but I’m not sure that’s a huge advantage. Best for infrequent hand soldering configuration.
Finally, zero ohm resistors seem best if a pick and place machine is going to be configuring the jumper settings. You just have to manage the BOM and DNI/DNP/DNS flags for the components.
EEschem & PcbNew have symbols for GS2 & GS3 solerable bridges.
These are both “Normally Open” but to close them you can just draw a wire / pcb over them and they will be “Normally Closed”.
When I used them on the PCB I noticed that they need quite a bit of solder and I would prefer a narrower gap.